What regulations apply to livestock vehicles?

All livestock vehicles must comply fully with the EC Regulations 1/2005 and any guidance notes relating to it. They must be accompanied by an attendant except where permitted by derogation. All livestock vehicles over 3.5 tonnes GVM must be fitted with lashing points on all routes.

What are the scenarios where a livestock vehicle may be refused carriage?   

This could happen if: 

Your vehicle doesn't comply with the relevant regulations and the guidance notes relating to it.  

The Master of the ferry believes hot or inclement weather, or adverse sea conditions, would cause suffering to animals on board.